A natural gas hydrate has the advantages of large reserves, wide distribution, high energy density, cleanness, environmental friendliness and the like, over the past decade, basic researches on the natural gas hydrate have been greatly developed, and abundant natural gas hydrate distribution has been found in seabed sediments and permafrost zones around the world. If the natural gas hydrate can be scientifically and reasonably developed and utilized, great strategic significance is played for perfecting the energy structure, protecting the environment and promoting the economic and social sustainable development.
Natural gas hydrate reservoir is characterized by low permeability, deep buried depth, complex gas components, etc. Meanwhile, hydrate development is closely related to deepwater technology, only a few countries in the world master this technology at present, the development and simulation research on the natural gas hydrate are bound to actively promote the rapid development of deepwater technology from the side and play an important role in the development of such resources as deepwater oil and gas and the like. Due to the invisibility and complexity of the hydrate exploitation process, only a comprehensive effect of multiple process parameters can be tested by an exploitation field test in general, and moreover, underground formation parameters cannot be directly measured at present. Therefore, the field test is not a completely ideal, economical and scientific test method. Description on the natural gas hydrate reservoir only involves such aspects as hydrate occurrence, reserve estimation and the like, but quantitatively accurate description still cannot be achieved; proposed exploitation modes of the natural gas hydrate reservoir are basically laboratory simulation, and understandings on exploitation mechanisms and dynamic exploitation conditions are rather superficial. Based on such special characteristics of the natural gas hydrate as lower temperature, higher pressure, complicated decomposition phase change process and the like, the exploitation of the natural gas hydrate is greatly different from the traditional oil and gas exploitation, has greater technical difficulty, and involves in situ synthesis and precise description of the natural gas hydrate reservoir, drilling technology security control of hydrate bearing formation, economic and reliable hydrate exploitation technology and treatment and collection of produced gas and water. These processes are inseparable important parts of developing secure and efficient hydrate exploitation technology and are a continuous process. The existing natural gas hydrate experimental simulation device mainly involves two aspects of accumulation and decomposition of the hydrate and lacks researches on the aspects of drilling process and produced gas collection. Meanwhile, the in situ hydrate synthesis, the drilling process, the exploitation process and the produced gas collection process of the hydrate are a continuous and inseparable process in a natural gas hydrate exploitation simulation process, so that if these processes are simply separated for single researches, the research requirements of developing an economical and efficient hydrate exploitation technology are hard to satisfy.